Securing means for fore-end of autoloading firearm



June 23, 1959 R. CRITTENDON -:rAL 2,891,341

SECURING MEANS FOR FoRE-END oF AuToLoApING FIREARM Original Filed May 2, 1956 United States Patent ice SECURING MEANS FOR FORE-END OF AUTOLOADING FIREARM Lexie Ray Crittenden, Wilmington, Del., Ellis William Hailston, lli'on, N.Y., Philip Richard Haskell, Fairfield, Conn., and Robert Peter Kelly `and Wayne Edwin Leek, llion, N .Y.

Original application May 2, 1956, Serial No. 582,153.

Divided and this application 'September 20, 1957, Serial No. 685,304

4 Claims. (Cl. 42-75) This invention relates to an autoloading .firearm and more particularly to an autoloading shotgun which may be produced in the various conventional shot shell gauges and which will be capable in any gauge of handling the diversbity of various powered shot shells commercially available.

This application is a division of our application Serial Number 582,153, iled May 2, 1956, for Autoloading Firearm. t

There have been available for many-years autoloading shotguns which depend for their performance on utilization of the recoil `motion Vimparted to a movably mounted barrel bythe tiring of the shot shell. While such shotguns have enjoyed wide acceptance, they are expensive to manufacture, for great care must be employed in their construction to insure that the recoil movement of the barrel is accurately guided and that the forces generated in stopping that recoil motion are adequately absorbed. Further, the motion of the barrel and the consequent redistribution of the recoil forces are disturbing to some shooters. There have been attempts, as exemplified by U.S. Patent No. 2,482,880, to operate an autoloading shotgun by means of gas pressure derived from the shot shell propellant. Insofar as we are aware, such designs have not been commercially acceptable and it is believed that diihculty may have been found in adapting this principle to successful operation with a range of high-powered and low-powered shot shells with which a commercial design must be capable of operating.

It is the principal object of this invention to produce an improvement in the means of securing the fore-end of an autoloading shotgun.

In order to accomplish this result, we propose to utilize to the greatest possible extent complete assemblies and individual parts commercially available as parts of an existing fixed barrel manually operated repeating shotgun. Such a manually operated shotgun is illustrated in U.S. Patent No. 2,645,873, and the fire control assembly which is an important component thereof is illustrated in detail in U.S. Patent No. 2,675,638. We contemplate that this manually operated shotgun may be best converted to autoloading operation by the utilization of operating power derived from two sources. One of these sources of power is the excess energy contained in the charge of expanding gas which forces the shot pellets through the barrel of the shotgun. We propose to tap this source of power by providing a gas port communicating with the barrel in the manner of the conventional gas operated firearm and to apply the gas thus vdiverted from the barrel to provide part of the force needed to operate the autoloading mechanism. The other source of power is that found in the inertia effects resulting from the recoil of the gun as a whole and the stoppage of that recoil by the opposition provided by the shooters shoulder. By the proper utilization and proportioning of these two sources of power, We have been able to produce an autoloading shotgun which, with a 2,891,341 Patented June 23, 1959 minimum of manual adjustment, functions adequately and dependably with the full range of various powered shot shells commercially available in the appropriate gauges, extending from the relatively low-powered loads provided for trap shooting to the heaviest hunting loads. In 12 gauge, the range is from 2% to 4 dram equivalent powder charge with l to 11/2 ounces of shot.

The exact nature of the invention, including several refinements in detail as well as other objects and advantages thereof, will `become apparent from consideration of the following specification, Areferring to the attached drawing in which:

Fig. 1 is a longitudinal vertical sectional view through a shotgun produced in accordance'with our invention.

Fig. 1a is an enlarged fragment of Fig. l.

Fig. 1b is also an enlarged fragment of Fig. l.

Fig. 2 is a cross-section on the line 2 2 of Fig. la.

Referring to the drawing, it will be seen that the shotgun illustrated therein corresponds generally to that shown in U.S. Patent No. 2,645,873 referred to above. It will be noted that ythe shotgun comprises a receiver 1 having a counterbore 2 in which there is received a barrel extension 3 secured to or integral with a barrel 4. A magazine tube 5 separated from the barrel by a small space extends into the receiverin axial parallelism with theV barrel and is ridigdly secured to the receiver as by a furnace or induction brazing operation. The magazine tube houses the usual magazine follower 6 and follower spring 7, the latter abutting at its forward end against a magazine spring stop 8 secured in place by a crosspin 9 or a crimped impression in the magazine tube. A barrel guide ring 10 is secured to the barrel 4 in position to embrace the forward end of the magazine tube when the barrel extension is seated in the receiver. Assembly of the barrel to the receiver is maintained by a magazine cap 11, which threadably engages the magazine tube and bears against the forward face of the barrel guide ring 10. The cap is releasably retained in position by a springJurged detent plunger housed in the barrel guide ring and engageable with serrations 12 in the rear face of the magazine cap. As the description proceeds, it will become apparent that this construction permits taking down the gun or replacing barrels without disturbance or dissembly of the gas cylinder, piston or other internal working parts.

A wooden fore-end 13 having a substantially U shaped cross-section (see Fig. 2) substantially encloses the magazine tube and the free ends of the U close the space between the magazine tube and the barrel 4. This Wooden fore-end is secured in place by a resilient rubber-like fore-end ring washer 15 engaged by the rear face of the barrel guide ring and urging a fore-end ring 14 having an undercut conical rear face into secure engagement with an undercut forwardly facing abutment 16 formed in that portion of the Wood of the fore-end enclosing the magazine tube. At the rear end of the fore-end an angularly disposed tenon 17 or beveled edge of the fore-end 13 is received in a matching cut in the forward face of the receiver 1 (see Fib. lb). The interengagement of the tenon 17 with the receiver cut and the similar inter-engagement of the fore-end ring 14 with the undercut abutment 16 provides reinforcement to the wooden fore-end and prevents splitting thereof without requiring the usual provision of a metal liner cemented therein and thereby permits a substantial saving in weight. Within the receiver 1 a breech bolt slide 18 is mounted for fore and aft reciprocation and guided by means which 'will later be described. This slide 18 is provided with a substantially rectangular lug 19 which is received within an aperture 20 formed in the body of a breech bolt 21. As in the patent previously referred to, a locking block 22 is also received in this aperture and has the function gaged with a suitably shaped recess in the barrel extens'ion. An operating handle 24 passes, r horizontally through va clearance aperture in the sidewall of the breech bolt into engagementv with the breech bolt slide and isy there releasably retained by means of a spring-urged detent plunger 25.

For further detailed description of the shotgun to which this invention is applied, reference may be made to the patent of `which this is a division. Although we have shown and described here only one specic embodiment of o ur invention, it will be apparent that the scope of our invention is not limited to that exact embodiment. For a definition of the limits which we conside; applicable to our invention, reference may be made to the appended claims.

We claim:

1. Ina rearm having a barrel, a receiver, a magazine tube extending forwardly from secured relation to the receiver in parallelism with said barrel and separated therefrom by a space, and a wooden fore-end of U- shaped cross-section embracing the magazine tube and also enclosing the space between the barrel and the magazine tube, the improvement in securing means for said fore-end comprising in combination a tenon on the rear end of said fore-end, a recess in said receiver to receive said tenon, an annular ring on said magazine tube having a rear face formed to dene a rearwardly and outmagazine tube to place said fore-end in longitudinal and wardly flaring conical surface,`an undercut surface on the inside of said fore-end, Vsaid surface being formed to dene a forwardly and inwardly tapering abutment extending circumferentiallyiv at least partially around the magazine tube embracing portion of the fore-end and adapted to be received in said conical surface of the ring, and means urging said ring rearwardly on said radially inward compression between said ring and said receiver. Y

2. The combination described in claim 1, said means l urging the ringv rearwardly including a yieldable resilent member acting on the forward face of said ring.

3. The combination described in claim 2 said yieldable resilient member consisting of a ring washer of resilient, rubber-like material encircling said magazine tube and placed in longitudinal compression. i

4. The combination described in claim 3, said meansJ urging the ring rearwardly including a depending barrel tudinal compression.

No references cited. 

